Banner Image: Glanville fritillary butterfly. By Charlesjsharp (Own work, from Sharp Photography, sharpphotography), CC BY-SA 4.0, Source, via Wikimedia Commons.


The Bailiwick of Guernsey is a British Crown Dependency, but is not part of the UK or of the EU. However, the UK Government is constitutionally responsible for its defence and international representation. The Bailiwick of Guernsey consists of the main island of Guernsey and several smaller islands including Herm, Jethou, Brecqhou, and Lihou, as well as the self-governing Alderney and Sark.

Guernsey has a varied landscape of town, villages, rolling farmland, ponds and marshes. Copyright: Dr Mike Pienkowski

Along with the separate Bailiwick of Jersey, it constitutes the archipelago of the Channel Islands, located in the English Channel to the north-west of the France, at 49 28 N, 2 35 W.

Its land area is 78 square kilometres. Its population was estimated at 66,502 in July 2017. The climate is temperate with mild winters and cool summers.   

The landscape of the main island is predominantly flat with some low hills in the southwest. 

Guernsey has many historic sites, including Le Creux ès Failes, a prehistoric passage grave, built during the Neolithic period (3000 to 2500 BC) and in use until the Late Bronze Age (ca 1000 BC). The grave is 9 m long, with the entrance shown above. Copyright: Dr Mike Pienkowski

Alderney is part of the Bailiwick of Guernsey, but it is self-governing and has its own assembly, the States of Alderney.

Also self-governing is Sark is the smallest of the Channel Islands covering 5.44 square kilometres.

Copyright: Dr Mike Pienkowski
One of the harbours, with boats grounded for much of the tidal cycle, illustrates the huge tidal range of the Channel Islands. Copyright: Dr Mike Pienkowski

The islands' 10-metre tides provide a large littoral zone, supporting a wide range of marine species and many species of waders (shorebirds).

A family of shelducks, one of the species favouring coastal areas. Copyright: Dr Mike Pienkowski

Some marine habitats include eelgrass beds (which provide spawning grounds for species such as sea bass and black sea bream), maerl beds and tidal rapids. These coastal areas are breeding sites for thirteen species of seabirds. Lesser black-backed gull found here represents a significant proportion of the regional populations.

Copyright: Dr Mike Pienkowski
Great black-backed gull on nest. Copyright: Dr Mike Pienkowski

Migrating land-birds, such as wheatears and pipits, rest in the dune grassland, whilst inland fragments of threatened wet meadow habitat are managed for their summer display of orchids and other rare plants. In the fragmented woodland, warblers, long-eared owl, and short-toed treecreeper breed.

Copyright: Dr Mike Pienkowski
Orchid.  Copyright: Dr Mike Pienkowski

On the cliff-land, the maritime grassland supports the rare Glanville fritillary butterfly and the cliff-top scrub hosts resident Dartford warbler, stonechat and many species of migrant bird, which use Guernsey as a vital refuelling stop in spring and autumn.

With its mild climate, Guernsey boasts nearly 2000 species of plants, which in turn support a diverse range of invertebrates, many absent from the UK. Guernsey features dramatic cliffs with nesting seabirds, including puffins, steep wooded valleys running down to the sea, and quiet rural lanes. The characteristic earth bank hedgerows are home to endemics such as Guernsey vole, greater white-toothed shrew, and Guernsey fern.

Lihou Island and the surrounding headland and wetland has been designated as a Ramsar Convention Wetland of International Importance. A second Ramsar Site, comprising Herm, Jethou & The Humps, has since also been designated.

Copyright: Dr Mike Pienkowski
Above: Part of Lihou Island & L'Eree Headland Ramsar Site. Below: Part of Herm, Jethou & The Humps Ramsar Site. Copyright: Dr Mike Pienkowski

Copyright: Dr Mike Pienkowski

The key governmental and non-governmental bodies involved in nature conservation in Guernsey are:

States of Guernsey

La Société Guernesiaise 

Guernsey Biological Records Centre   

Guernsey faces many conservation challenges. Locally, increased urbanization, disturbance, invasive non-native species, and land management changes are all factors. Like all other nations Guernsey, is affected also by climate change, pollution and conflicting policy objectives.

Copyright: Dr Mike Pienkowski
Sailing boat off the island's capital, St Peter Port. Copyright: Dr Mike Pienkowski

In an attempt to improve the Island's biodiversity, local authorities have implemented a new system of farm subsidy. This programme aims to make farming less intensive and encourages farmers to undertake various conservation measures.

Cattle and crops. Copyright: Dr Mike Pienkowski

The Biodiversity Strategy for Guernsey outlines these challenges and the policy initiatives designed to overcome them.

Copyright: Dr Mike Pienkowski
A rocky part of the coast. Copyright: Dr Mike Pienkowski

The Biodiversity Strategy recognises that local legislation to protect the Island biodiversity is limited. The current planning laws contain enabling powers, which allow for the control of development on land, and there is also provision in the main Planning Law to designate Sites of Special Significance (SSSs). The Biodiversity Strategy outlines the course of action that would be needed for the Convention of Biological Diversity to be extended to it.

A virtual tour for Guernsey, outlining its historical and cultural importance is in draft and will be available here in due course.